1. Field of the Invention
The present invention relates to a condenser lens having a novel structure, more particularly, the invention relates to a discontinuous light-beam condenser lens which can be ideally used for a solar-beam condensing furnace and the like.
2. Description of Related Art
In the field of solar-beam condensing furnace for extracting light energy by condensing solar beams, a variety types such as reflection type or direct permeating type have been used.
A solar-beam-reflection-type furnace making use of a reflection mirror does not only generate much loss of solar energy, but it is also difficult to conduct work on conversing line of solar energy and to control sun-following, and yet, there have been such problems that the furnace itself become larger and a huge amount of capital spending is required.
There have been various methods for utilizing solar beams by condensing solar beams onto a single line with the use of an optical lens. However, in such conventional methods with the use of a convex lens, since the convex lens itself has upper-lower symmetrical convex curve surfaces from its structural viewpoint, it has caused a high reflection factor against incident light, and has worsened efficiency of incident-light permeability. In addition, the condensed beams are varied widely so as not to be condensed onto a single line. Further, a convex lens used in such conventional methods had to be large to receive solar beams in a wide range and its center portion was thicker than the other portions, it did not have enough strength to be practically used.
In order to solve the above problems, the Japanese Laid-Open Patent Publication No. 62-225851 (1987) discloses a condenser unit comprising a plurality of thin fan-shaped convex lenses combined concentrically to each other with flat light-incident surfaces having a minimum reflection factor. However, the above condenser unit was not capable of condensing solar beams onto a single line, but it was merely a convex-lens-applied condenser unit.